<?php
    /**
    * 返回一个缩略的名字
    *     echo tiri_imgae_get_thumb_name('20111022092629_22201.png');
    * 
    * @param mixed $image_name
    */
    function tiri_imgae_get_thumb_name($image_name){
        $fileParts = explode( ".", $image_name );
        if(count($fileParts) ==1 ){
            return $image_name.'_smail';
        }
        $ext = array_pop($fileParts);
        $file_name = implode('.',$fileParts);
        return $file_name.'_small.'.$ext;

    }

    if(!function_exists('tiri_image_resize'))
    {
        /**
        * 缩小图片
        * 
        * @param mixed $src_file
        * @param mixed $dst_file
        * @param mixed $dst_width
        * @param mixed $dst_height
        */
        function tiri_image_resize($src_file, $dst_file, $dst_width=100, $dst_height=100) { 

            if(!function_exists('imagecreate')){
                return false;
            }
            if($dst_width <1 || $dst_height <1) { 
                echo "params width or height error !"; 
                return false;
            } 
            if(!file_exists($src_file)) { 
                echo $src_file . " is not exists !"; 
                return false; 
            } 

            $type=exif_imagetype($src_file); 
            $support_type=array(IMAGETYPE_JPEG , IMAGETYPE_PNG , IMAGETYPE_GIF); 

            if(!in_array($type, $support_type,true)) { 
                echo "this type of image does not support! only support jpg , gif or png"; 
                return false;
            } 

            switch($type) { 
                case IMAGETYPE_JPEG : 
                    $src_img=imagecreatefromjpeg($src_file); 
                    break; 
                case IMAGETYPE_PNG : 
                    $src_img=imagecreatefrompng($src_file); 
                    break; 
                case IMAGETYPE_GIF : 
                    $src_img=imagecreatefromgif($src_file); 
                    break; 
                default: 
                    echo "Load image error!"; 
                    exit(); 
            } 
            $src_w=imagesx($src_img); 
            $src_h=imagesy($src_img); 
            $ratio_w=1.0 * $dst_width/$src_w; 
            $ratio_h=1.0 * $dst_height/$src_h; 
            if ($src_w<=$dst_width && $src_h<=$dst_height) { 
                $x = ($dst_width-$src_w)/2; 
                $y = ($dst_height-$src_h)/2; 
                $new_img=imagecreatetruecolor($dst_width,$dst_height); 
                imagecopy($new_img,$src_img,$x,$y,0,0,$dst_width,$dst_height); 
                switch($type) { 
                    case IMAGETYPE_JPEG : 
                        imagejpeg($new_img,$dst_file,100); 
                        break; 
                    case IMAGETYPE_PNG : 
                        imagepng($new_img,$dst_file); 
                        break; 
                    case IMAGETYPE_GIF : 
                        imagegif($new_img,$dst_file); 
                        break; 
                    default: 
                        return false;
                        break; 
                } 
            } else { 
                $dstwh = $dst_width/$dst_height; 
                $srcwh = $src_w/$src_h; 
                if ($ratio_w <= $ratio_h) { 
                    $zoom_w = $dst_width; 
                    $zoom_h = $zoom_w*($src_h/$src_w); 
                } else { 
                    $zoom_h = $dst_height; 
                    $zoom_w = $zoom_h*($src_w/$src_h); 
                } 

                $zoom_img=imagecreatetruecolor($zoom_w, $zoom_h); 
                imagecopyresampled($zoom_img,$src_img,0,0,0,0,$zoom_w,$zoom_h,$src_w,$src_h); 
                $new_img=imagecreatetruecolor($dst_width,$dst_height); 
                $x = ($dst_width-$zoom_w)/2; 
                $y = ($dst_height-$zoom_h)/2+1; 
                imagecopy($new_img,$zoom_img,$x,$y,0,0,$dst_width,$dst_height); 
                switch($type) { 
                    case IMAGETYPE_JPEG : 
                        imagejpeg($new_img,$dst_file,100); 
                        break; 
                    case IMAGETYPE_PNG : 
                        imagepng($new_img,$dst_file); 
                        break; 
                    case IMAGETYPE_GIF : 
                        imagegif($new_img,$dst_file); 
                        break; 
                    default: 
                    return false;
                        break; 
                } 
            } 
            return true;
        } 
    }
?>
